A storage area network (“SAN”) permits the distribution of components, such as servers, storage devices and storage controllers, to provide a customer with access to a large storage pool. FIG. 1 is a block diagram of a generic SAN 100. Controllers 102 may be shared among multiple servers 104. In one type of SAN, the components are interconnected using the Fibre Channel protocol. The components (also referred to as nodes) may be interconnected directly (a point-to-point topology), in a ring (an arbitrated loop topology) or through switches (a switched fabric topology). The term “switch” is used herein generically to refer to switches, directors, hubs, bridges and the like. Using switches, data may be delivered across the fabric 106 from any source (or initiator) node to any destination (or target) node.
Each node is given a unique 8-byte address (a “world wide node name” or WWNN) which is assigned by the manufacturer in accordance with an established IEEE standard. Each port in a node is also given a unique 8-byte address (a “world wide port name” or WWPN) by the manufacturer.
In part to reduce the space in a channel frame header required to address a particular port and thus speed up routing of data, another port addressing scheme was developed. After a connection has been established between a node and a switch, each port in the node is assigned a unique (within the fabric) address (destination_id) by a controlling switch using a name server. The switch maintains a translation between the port address and the WWPN address and can address any port in the fabric using the destination_id. Additionally, each slot of a node has a “name” (interface_id) by which the slot may be physically identified.
However, because there may be no correlation between a port address and the physical slot location of the port, a human administrator may find it difficult to determine to which port of a node a cable should be connected. Consequently, a need exists for easily determining which physical slot on a node corresponds with a port address.